1. Field of the Invention
This invention relates generally to tape cassettes, and particularly to tape cleaning means incorporated into such cassettes.
2. Description of the Prior Art
If recording or reproducing of data is performed in a magnetic tape cassette system, dust or other debris may invade the cassette and get onto the tape recording surface, thereby causing so-called soft errors, or drop-out, to occur in the output signal. To prevent occurrence of such output-signal errors in magnetic disk systems, U.S. Pat. No. 4,149,207, issued Apr. 10, 1979 to Porter, Jr. et al., discloses a disk cleaning means for a disk cassette. The cleaning means in that patent comprises a flexible cleaning tab having a backing layer of Mylar (registered trademark of E. I. duPont de Nemours & Co.) film or the like covered by a porous fibrous paper cleaning layer. One end of the tab is mounted in a V-shaped rib on the cassette wall; the other end is biased into engagement with the disk face to clean it.
A disk cleaning means for a disk cassette also is disclosed in U.S. Pat. No. 4,510,546, issued Apr. 9, 1985 to Asami et al. The cleaning means there comprises a flexible pressure member interposed between a cleaning liner and a wall of the cassette for pressing a surface portion of the cleaning liner against the recording surface of the disk.
A device for cleaning motion-picture film is disclosed in U.S. Pat. No. 1,176,483, issued Mar. 21, 1916 to J. J. Ormsby. That device, for cleaning each film roll, comprises a pad of felt material secured to a cylindrically curved concave surface of a shoe, with a cleaning strip of fabric stretched across the arc of the shoe. The cleaning strip on each shoe is pressed into engagement with the outer winding of one of the film rolls, to clean the film as it is unwound from one roll and wound onto the other.